Loeb's Third Point Offshore Fund Ltd has requested permission from the U.S. consumer protection regulator to acquire shares in the company above a certain threshold, according to the filing dated March 23 on the FTC's website.

United Tech declined to comment and Third Point was not immediately available for comment.

The company's shares have lagged the broader market under Chief Executive Officer Greg Hayes as the company spent heavily on developing a new fuel-saving geared turbofan aircraft engine and as sales of Otis elevators were pressured by a supply glut in China.

Billionaire investor William Ackman's Pershing Square Capital Management is also building a position in United Tech, according to reports in February. (Reporting by Ankit Ajmera in Bengaluru; Editing by Bernard Orr)